Rear wiper not working

[Oddjobber_the_1st]

Hello, I have got an MG ZT-T 2.5L V6 190+ 2001 reg. The other day the rear wiper stopped working but after checking the fuses I could not find any problems. All the fuses in the box in the engine compartment were all changed, also all the fuses were replaced in the box under the glove box. I inspected all the fuses that were removed only to find that none had failed, and the contacts were clean. When I tried the wiper again it still did not work, even with the new fuses. So my next thought was that it could be the motor, so I bought a reconditioned one that was guaranteed to be in full working condition. I found that I could not pen the tailgate window to remove the old one. This was a new fault that wasn't there before the motor stopped working. I plugged the new motor into the electrical connectors for the motor, and while holding it and someone working the switch on the stalk I tried the new motor out. I found that the new one didn't work either even though guaranteed. I took the motor to our closest motor electricians place and they tried the new and old motor, they both worked. So basically I need help with, how I can open the tailgate window without smashing it, and also is there something I could try to see if there is someI have missed. Any help would be very gratefully appreciated.
Kindest regards, Alan

[SD1too]

Hello Alan,

Looking at the circuit diagram there's a switch which tells the BCU when the tailgate glass is open. It could be that this prevents the rear wiper from receiving a supply and if faulty would explain why both original and replacement motors are not working.

If you have a multimeter you could check for 12v on the white/green wire at the rear wiper relay when the stalk is operated. If it's not present we'll be onto something.

Simon

[WillyHeckaslike]

I'm not familiar with how the tourer is wired but a common problem on other hatchbacks is fatigue and fracture of a wire or more within the loom connecting the tailgate to the body of the car. The loom flexes where it is routed near to the tailgate hinges and it flexes every time the tailgate is moved. In time internal fractures occur within the individual cables and the fractures are quite often not visible to the eye being internal and covered by the insulation. Failure of the rear wiper motor to operate can be a symptom of this but it can sometimes give rise to other electrical problems which can appear to defy logic.

Flexing the loom by hand where it hinges can sometimes reveal if a fracture is present as it may cause the fracture to make contact and the wiper motor might move as a result. If not then a closer inspection and fiddle of the loom after pulling back the rubber covering boot might show something. I have this problem atm with my Rover 25, I've had it for a few years now but yet to find the time and the opportunity to sort it. I've got by so far by a combination of flexing the loom as mentioned above and sometimes moving the tailgate when the wiper stops working. My car sees little use these days so while I have been able to suffer the inconvenience of this happening it might not be so for everyone.

[Southcoaster]

With mine, the shaft through the glass had seized. Removing and cleaning it solved the problem.

[Oddjobber_the_1st]

Hello, thank you all, it wax indeed a fractured wireto when motor, the wiper now works just how it should, still unable to open the glass though. My son put power to the latch and it opened, so we wired up a live to the latch, which worked once and again I am unable to open the glass, guess I will just carry on without it opening. The problem that I have is that if something should work I want it to work, just a quirk I guess in my dna.
Thank you all again, regards, Alan

[Devilish]

Seems you have another break in the wiring, should be no harder than diagnosing the wiper wire fault.